Smart Cards (SC) are widely used in conjunction with security measures such as authentication and encryption. For example, in order to access a computerized device and to access information by way of the computerized device, one may have to couple a smart card to the computerized device. Access to the computerized device and to information may be granted following a successful interaction between the computerized device and the smart card. The interaction may involve user input.
A smart card reader (SCR) is a device that can communicate with both the SC and the computerized device and can therefore be used to couple them. The SCR may include one or more driver applications to communicate with the SC and with the computerized device.
A process in the computerized device that needs to communicate with the SC can usually do so by way of a Cryptographic Service Provider (CSP) application, or a smart card driver, in the computerized device. The process sends a request to the CSP which generates the appropriate command to be passed to the SC. The CSP then sends the command to the SCR that in turn passes it to the SC. The SC may generate a response and pass the response to the SCR. The SCR sends the response to the computerized device and it is received by the CSP. The CSP then passes the response to the process from which the command originated.
Some smart card readers are designed to be permanently installed inside a computerized device such as a desktop computer. Other smart card readers, for example, those in the form factor of a PCMCIA (Personal Computer Memory Card International Association) card, are designed to be easily installable and removable at an appropriate bay in a mobile computerized device such as a laptop computer. Other smart card readers are designed to connect to a computerized device via an electrical cable.
In these three examples, the SCR is mechanically and electrically coupled to the computerized device. However, smart card readers that are mechanically disconnected from the computerized device and can communicate with the computerized device using wireless communication are known. Since a wireless smart card reader does not require mechanical coupling to the computerized device, it can in principle maintain parallel communication sessions with two or more computerized devices via the wireless communication.
In a common scenario, a single SC is coupled to a single SCR that is in turn coupled to a single computerized device. The CSP may maintain a continuous open communication with the SCR and over this communication it may maintain a continuous open communication session with the SC.
In another scenario, two or more computerized devices may be able to maintain communication with a single SCR and to attempt to share the services of a single SC that is coupled to the smart card reader. The secure nature of the SC requires that only one session between the SC and a computerized device be open at any given time. Once one computerized device establishes a communication session with the SC, other computerized devices may not be able to access the SC until this session is terminated. Consequently, operations in the other computerized device that require the use of the SC cannot be performed timely.
It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity.